I mean what is the best temperature and how many scans are needed to take a acceptable spectrum?
no needs special conditions. You must manipulate as a normal organic compound.
The number of scans will depend on the substrate concentration. I recommend you to scan and go looking in front of the software.
If you have a lot of free hidroxil groups, 3 or more, do with D2O or DMSO, if you do not, you can use CDCl3
I think it doesn't work. I tried to take the 13C-NMR of a cellulose derivative in DMSO-d6 at 30oC, but I couldn’t obtain an acceptable spectrum for 1000 scan (The concentration of my sample was 50mg/mL). I looked at literature and found they normally use of higher temperatures and more scans. I want to know what is the best condition?
Solid-state 13C CP-MAS NMR spectroscopy
http://www.lenzing.com/fileadmin/template/pdf/konzern/lenzinger_berichte/ausgabe_87_2009/LB_2009_Zuckerstaetter_5_ev.pdf
another option.... http://pubs.rsc.org/en/Content/ArticleLanding/2005/CC/b417745b#!divAbstract
Solid-state 13C NMR is a good way of doing things - if you have a decent amount of material you should run it by cross polarization MAS and also by direct 13C obsevation with inverse-gated decoupling as the CP-MAS experiment may not be quantitative. We have run lots of alginates, chitosans, celluloses, flours - you really have to worry about the molecular weight of the polysaccharide or you will get crappy results - there is often a depolymerization step you need to perform with acid and then a readjustment of the pH. Also your concentration will be critical for 13C. Were you trying to do quantitative 13C or just qualitative by HMQC/HMBC?
I just want to get a qualitative 13C-NMR of a chitosan derivative. Also, solid state NMR is not available in our country.
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